package hacker_rank.mar14;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class XorNinja {
	static final int k = 10 ^ 9 + 7;

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int T = Integer.parseInt(br.readLine());
		for (int t = 0; t < T; t++) {
			int N = Integer.parseInt(br.readLine());
			String[] line = br.readLine().split(" ");
			int[] nums = new int[N];
			for (int i = 0; i < N; i++) {
				nums[i] = Integer.parseInt(line[i]);
			}

			solve(nums);
		}
	}

	static void solve(int[] nums) {
		Set<Integer> set = new HashSet<Integer>();

		for (int i = 0; i < nums.length; i++) {
			set.add(nums[i]);
		}

	}

	static void powerSet2(int[] arr) {
		for (int i = 0; i < arr.length; ++i) {
			int[] branch = new int[i];
			combine(arr, i, 0, branch, 0);
		}
	}

	static void combine(int[] arr, int k, int startId, int[] branch, int numElem) {
		if (numElem == k) {
			System.out.println(Arrays.toString(branch));
			return;
		}

		for (int i = startId; i < arr.length; ++i) {
			branch[numElem++] = arr[i];
			combine(arr, k, ++startId, branch, numElem);
			--numElem;
		}
	}

	public static Set<Set<Integer>> powerSet(Integer[] originalSet) {
		Set<Set<Integer>> sets = new HashSet<Set<Integer>>();
		if (originalSet.length == 0) {
			sets.add(new HashSet<Integer>());
			return sets;
		}

		List<Integer> list = Arrays.asList(originalSet);
		Integer head = list.get(0);
		// Set<Integer> rest = new HashSet<Integer>(list.subList(1,
		// list.size()));
		Integer[] rest = new Integer[list.size() - 1];
		list.subList(1, list.size()).toArray(rest);
		for (Set<Integer> set : powerSet(rest)) {
			Set<Integer> newSet = new HashSet<Integer>();
			newSet.add(head);
			newSet.addAll(set);
			sets.add(newSet);
			sets.add(set);
		}
		return sets;
	}

}
